Pressure fluid motor



March .8, 1938. E, Q GAR-HN 2,110,331

PRESSURE FLUID MOTOR Filed July 17, 1955 2 Sheets-Sheet l m v v v v J4 M 7///// g WWW/A lumi,

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March 8, 1938. E. G. GARTIN l '2,110,331-

PRESSURE FLUID MOTOR Filed 'July 17, 1953 2 sheets-sheet? I F1/'g2 v J0 5 j@ 4 6m gf Patented Mar. 8, 1938 PATENT OFFICE PRESSURE lFL'l'lIl')v MOTOR Elmer G. Gartin, Claremont, N. 11., assignor to Sullivan Machinery Company, a corporation of Massachusetts Application July 17, 1933, Serial No. 680,798

16 Claims.

My invention relates to pressure fluid motors, and more particularly to improvements in the fluid distribution means of such motors.

An object of this invention is to provide an improved pressure fluid motor. Another object is to provide an improved fluid distributing means for such a motor. Still another object is to provide an improved valve mechanism for a pressure fluid motor, the valve mechanism and dis- '10 tribution passages controlled thereby being arranged Within the motor piston in an improved manner whereby the speed and efficiency of the motor may be materially increased. A still further object is to provide an improved valve mechanism arranged within the motor piston of a pressure fluid motor of the reciprocating piston impact type. These and other objects and advantages of the invention will, however, hereinafter more fully appear.

In the accompanying drawings there are shown for purposes of illustration three forms which the invention may assume in practice.

Fig. 1 is a longitudinal section through one illustrative embodiment of the improved pressure uid motor.

Fig. 2 is a view similar to Fig. 1, showing the motor piston and fluid distributing valve in a diiferent position.

Fg. 3 is a cross sectional View taken on line 3-3 of Fig. 1.

Fig. 4 is a cross sectional view taken on line 4--4 of Fig. 2.

Fig. 5 is an elevational View showing the distributing valve.

Fig. 6 is a View similar to Fig. 1, showing a modied form of construction, with the section on line 6 5 of Fig. 8.

Fig. 7 is a View similar to Fig. 6, showing the motor piston and fluid distributing valve in a different position, and with piston rotated to the angle of line `I-'I.

Fig. 8 is a cross sectional view taken on line 8-8 of Fig. 6.

Fig. 9 is a cross sectional view taken on line 9-9 of Fig. '7.

Fig 10 is an elevational View of the modified form of fluid distributing valve.

Figs. 11 and 12 are fragmentary sectional views, similar to. Figs. 6 and '7, showing a still further modified form of valve construction.

In the illustrative embodiment of the invention shown in Figs. 1 to 5, inclusive, there is shown a pressure iluid motor of the uid actuated, reciprocating piston type, comprising a cylinder I having a bore 2 containing a reciprocable motor piston 3, herein in the form of a hammer having a front striking projection 4 adapted to transmit a seriesl of impact blows through a striking block 5 to the shank 6 of a working implement. The shank 6 is arranged in a chuck l carried within a chuck housing 9 arranged at the forward end of the cylinder and forming the front cylinder head. Secured to the rear end of the cylinder is. a rear cylinder head block III, and the elements 9, I and I0 are secured in assembled relation in any suitable manner. Arranged transversely in the head block I0 is a bore I I containing a rotary throttle valve I2, and this throttle valve controls the flow of pressure fluid through a passage I 3 to a constant pressure chamber Ill in the form of a bore formed in axial alinement with the cylinder axis. Alined with the bore I4 is a reduced bore I5 for guiding a tubular projection I6, herein formed integral with a valve chest element II, herein threadedly connected at I8 Within the rear end of the hammer piston. Formed in the hammer piston is a valve chamber I9 containing a reciprocable fluid distributing valve 20. The Valve 20 is herein in the form o-f a at disc having a central opening 2l. Formed in the forward face of the valve chest member il are concentric annular grooves 22 and 23, and the inner groove 23 communicates with an axial bore 24, formed in the tubular projection I6, through slots 25 while the outer groove 22 communicates with the rear end of the cylinder bore through a series of passages 26 formed in the member I'l. Also formed in the front Wall of the valve chamber are concentric annular grooves 21 and 28, of the same diameter as the grooves 22 and 23; While formed centrally therein is a recess or chamber 29 communicable through the opening ZI in the valve with the fluid supply passage 24, The inner groove 28 communicates with the chamber 29 through slots 38, while the outer groove 2l communicates with the forward end of the cylinder bore through a series of passages 3| formed in the piston head. The cylinder has formed therein a central, piston-controlled, free exhaust port 32.

In this form of the invention, when the parts are in the position shown in Fig. 1, pressure uid flows through supply passage I3, constant pressure chamber I4, the axial supply passage 24 formed in the tubular projection I6, to the Valve chamber at the rear side of the Valve, and thence through the outer groove 22, and the passages 26, to the rear end of the cylinder bore; the pressure fluid acting on the rear face of the piston head to drive the piston in a forward direction to effect its working stroke. When the'rn'otor piston is .in the position shown in Fig. 1, the forward chamber 29, and thence through the s1ots'30 to` thek inner annular groove 28, and then acts on the forward face of the valve being opposed by a reduced pressure, thereupon throws the valve rearwardly from the position shown vin Fig. 1

`to the position shown in Fig. 2. yWhen the parts are in the position shown in Fig. l2, pressure fluid flows through the axial supply passage 24, through the passage 2 I, through the valve chamber atthe forward side of the valve, and thence through the outer annular groove 21 and passages 3I to the frontend of the cylinder bore;

the pressuregiluid acting on the forward face of the piston head to move the piston rearwardly to effect the retraction stroke. When the parts are in the position shown in Fig. 2, the rear end of the cylinder bore is connected to exhaust through the exhaust port 32. As the piston moves rearwardly, the forward edge of the piston head overruns the exhaust port 32, thereby connecting the forwardl end of the cylinder bore to exhaust, and thereafter the pressure in the annular groove 23 acting on the rear face of the valve throws the valve against the opposing reduced pressure, from the position shown inV Fig. 2 to the initial position shown in Fig. 1. These events are repeated in rapid succession during normal operation of the motor.

Infthe modified form as shown in Figs. 6 to 10, inclusive, the motor cylinder and head structure are identical to those in the form described above. In this form of the invention, however, the fluid distribution passages are so arranged that when the motor piston strikes the striking block 45 there is no tendency `for the valve to be thrown off its seat by the inertia action. In this form of the invention, the rear face of the valve chest member with which the projection I6 is integrally formed, is provided with an annular groove 36 communicating with the supply passage 24 by slots 31. Formed in the piston, in front of the member 35, is a valve chamber 39, and the front wall of this valve chamber is i provided with an annular groove 39 communieating with an axial chamber 40 through slots 4I. `In this form of the invention, the valve is of the spool type, having a peripheral guide sleeve portion 42 and a central sleeve portion 43 having an axial opening 44 alined with the axial supply passage 24 and forming a passage for conducting pressure fiuid from the passage 24 to the chamber 40 at the forward side of the valve chamber. Formed inthe opposite faces of the valve are annular recesses 45 and 46, separated by a central transverse partition 41. Formed at the opposite ends of the valve chamber are annular grooves 48 and 49, the groove 49 being connected bya series of passages 50 with the rear end of the cylinder bore, and the groove being connected to the front end of the cylinder bore through` a series of passages 5I.

When the parts are in the position shown in Fig. 6, pressure fluid flows from the supply pas- Y sage I3 through the constant -pressure chamber I4, axial supply passage 24, passage 44 in the valve, and through the valve chamber at the forward face of the valve, and thence through groove 49 and passage 50 to the rear end of the cylinder bore; the pressure fluid acting on the rear face of the piston head to drive the piston forwardly to effect its working stroke. As the rear edge of the piston head overruns the exhaust port 32, the pressure fluid in the rear end of the cylinder bore .is conducted to exhaust, while the pressure fluid conducted by the axial passage 24 through slots 31 to the annular groove 36 acts on the rear face of the valve to throw the valve against the opposing reduced pressure from the position shown in Fig. 6 to the position shown in Fig. '7. When the striking portion of the motor piston engages the striking block, there is no tendency, in this form of the invention, for the valve to be thrown from its seat by the inertia action, since when the motor piston strikes its blow the valve is held firmly against thev front wall of the valve chamber. However, if the valve should, for any reason, not be thrown forwardly by the pressure fluid,` it is thrown by the inertia action when the piston strikes the striking block. When the parts are in the position shown in Fig. '1, pressure fluid flows through axial supply passage 24, through the valve chamber, past the rear face of the valve, thence through groove 48 and the 4passages 5I, to the front end of the cylinder bore, the pressure fluid acting on the front face of the piston head to drive the piston rearwardly to effect'its retraction stroke. As the forward edge of the piston head overruns the exhaust port 32, the front end of the cylinder bore is connected to exhaust, and as a result, the valve is thrown from the position shown in Fig. 7 to the initial position shown in Fig. 6 by the line pressure in the groove 39 acting against the opposing reduced pressure. Otherwise this form of the invention is identical to that described above.

In the modification shown in Figs. 11 and 12. the cylinder and piston structure andthe fluid distributing passages and valve chamber structure are similar to those shown inv Fig. 6. In this form of the invention, the rear face of the valve `chest member 52, with which the tubular member I6 is integrally formed, is provided with an annular groove 53 communicating with the axial supply passage 24 through slots 54. Formed in the forward wall of the valve chamber is an annular groove 55 communicating with an axial chamber 55 through slots 51. The fluid distributing valve is of the spool type, as in the form of the invention shown in Fig. 6, but in this instance the outer sleeve portion of ythe valve is provided with a radial flange 58 projecting outwardly from the outer of inner and outer sleeve-like, concentric flanges 59 and v6I). 'Ihe opposite faces of the valve are provided with annular recesses 6I and 62 formed between the concentric flanges, and these recesses are separated by a central transverse partition 63. In this form of the invention the line pressure acting in the groove 53 tending to throw the valve from the position shown in Fig. 11 to the position shown in Fig. -12, is supplemented by compression pressure built up in the forward end of the cylinder bore by the motor piston and acting on the rear pressure area of the radial flange 58. During rearward movementof the piston the valve is thrown from the position shown in Fig. `l2 to the position shown in Fig. 1l by the line pressure in groove 55 and compression pressure built up in the rear end of the cylinder bore by the motor piston and acting on the front pressure area of the flange 58. It will thus be seen that this form of valve is thrown by line pressure and compression pressure acting against an opposing reduced pressure. Otherwise this form of the invention is identical to that described above in the modification shown in Fig. 6.

As a result of this invention, it will be noted that an improved pressure fluid motor is provided, having an improved valve mechanism arranged within the motor piston and improved fluid distributing passages controlled thereby, whereby the speed and eiliciency of the motor vmay be materially increased due to the extremely short distances the motive fluid must flow between the valve and the working spaces. It will further be noted that the improved pressure lluid motor is of an extremely simple design, the arrangement of the valve within the motor piston enabling the use of relatively short supply passages in providing for a substantially direct llow from the valve chamber to the ends of the cylinder. These and other uses and advantages of the invention Will be clearly apparent to those skilled in the art.

While I have in this application specifically described three forms which my invention may assume in practice, it will be understood that these forms are shown for purposes of illustration only, and that the invention may be further modified and embodied in various other forms without departing from its spirit or the scope of the appended claims.

What I claim as new and desire to secure by Letters Patent is:

1. In a pressure fluid motor, a cylinder, a piston reciprocable therein, and fluid distribution means for effecting reciprocation of said piston including a valve chamber formed in said piston, a fluid actuated fluid controlling valve arranged in said chamber, and passage means controlled by said valve for supplying pressure fluid to said cylinder, said passage means arranged with respect to said valve and said valve being arranged in said chamber so that said valve seats in a forward position when the piston strikes its blow, thereby to prevent unseating of the valve by inertia action.

2. In a pressure fluid motor, a cylinder, a piston reciprocable therein, and fluid distribution means for effecting reciprocation of said piston including a valve chamber formed in said piston, a valve mounted in said valve chamber for controlling fluid llow to the opposite ends of said cylinder, and passage means for supplying pressure fluid from the valve chamber at the forward side of the valve to the rear end of the cylinder and from the valve chamber at the rear side of the valve to the forward end of the cylinder.

3. In a pressure fluid motor, a cylinder, a piston reciprocable therein, and fluid distribution means for effecting reciprocation of said piston including a valve chamber formed in said piston, a valve mounted in said valve chamber for controlling fluid flow to the opposite ends of said cylinder, passage means for supplying pressure fluid from the valve chamber at the forward side of the valve to the rear end of the cylinder and from the valve chamber at the rear side of the valve to the forward end of the cylinder, and fluid means for throwing said valve into its opposite operating positions.

4. In a pressure fluid motor, a cylinder, a piston reciprocable therein, and fluid distribution means for effecting reciprocation of said piston including a valve chamber formed in said piston, a fluid actuated .fluid distributing valve arranged in said valve chamber for controlling fluid flow to the opposite ends of said cylinder, passage means for supplying pressure fluid from the valve chamber at the forward side of the valve to the rear end of the cylinder and from the valve chamber at the rear side of the valve to the forward end of the cylinder, and fluid means for throwing said valve into its opposite operating positions.

5. In a pressure iluid motor, a cylinder, a piston reciprocable therein, and fluid distribution means for effecting reciprocation of said piston including a valve chamber formed in said piston,

a lluid actuated fluid distributing valve arrangedA in said valve chamber for controlling fluid flow to the opposite ends of said cylinder, passage means for supplying pressure fluid from the valve chamber at the forward side of the valve to the rear end of the cylinder and from the valve chamber at the rear side of the Valve to the forward end of the cylinder, and fluid means for throwing said valve into its opposite operating positions, said valve being thrown by line pressure acting on one side of the valve against an opposing reduced pressure.

6. In a pressure fluid motor, a cylinder, a piston reciprocable therein, and fluid distribution means for effecting reciprocation of said piston including a valve chamber formed in said piston, a iluid actuated fluid distributing valve arranged in said valve chamber for controlling iluid flow to the opposite ends of said cylinder, passage means for supplying pressure iluid from the valve chamber at the forward side of the valve to the rear end of the cylinder and from the valve chamber at the rear side of the valve tothe forward end of the cylinder, and fluid means for throwing said valve into its opposite operating positions, said valve being thrown by line pressure and compression pressure acting on one side of the Valve against an opposing reduced pressure.

7. In a pressure fluid motor, a cylinder, a piston reciprocabletherein, and uid distribution means for effecting reciprocation of said piston including a valve chamber formed in said piston,

passages connecting the opposite ends of said chamber to the ends of the. cylinder which are respectively more remote from said chamber ends, a fluid actuated sleeve valve arranged in said valve chamber for controlling fluid .ilow through said passages to the opposite ends of said cylinder and having inner and outer sleeve-like body portions providing between them annular grooves, one in each of the opposite faces of the valve, and providing seat areas of relatively large extent whereby diiferential pressures are exerted on the opposite ends of the valve in either end position of the latter, and means for supplying pressure fluid constantly to said grooves, said valve having an axial passage through which fluid flows for passage to one end of said cylinder, said constant pressure supply means for one of said grooves receiving pressure fluid flowing through said axial valve passage.

8. In a pressure fluid motor, a cylinder, a piston reciprocable therein, said piston having a rearwardly projecting tubular portion, and fluid distribution means for effecting reciprocation of said piston including a valve chamber formed in said piston, a fluid controlling valve arranged in said chamber for controlling fluid flow to the. opposite ends of said cylinder, passage means for supplying pressure fluid from the valve chamber at the forward side of the valve to the' rear end of the cylinder and from the valve chamber at the rear side of the valve to the forward end of the cylinder, and fluid supply means for said valve chamber including an axial passage formed in said tubular portion.

9. In a pressure fluid motor, a cylinder having a rear head, said head having formed therein a constant pressure chamber, a hammer piston reciprocable in said cylinder and having a rearwardly projecting tubular portion projecting Withinsaid pressure chamber, and fluiddistribution means for effecting reciprocation of said piston including a valve chamber formed in said piston,

a fluid controlling valve arranged in said valve chamber for controlling fluid'flow to the opposite ends of said cylinder, and passage means for supplying pressure fluid from the valve chamber at the forward side of the valve to the rear end of the cylinder and from the valve chamber at the rear side of the valve to the forward end of the cylinder, pressure fluid being supplied to said valve chamber from said constant pressure chamber through said tubular portion,

10. In a pressure fluid motor, a cylinder having a rear head, said head having formed therein a constant pressure chamber, a hammer piston reciprocable in said cylinder and having a rearwardly projecting tubular portion projecting within said pressure chamber, and fluid distribution means for effecting reciprocation of said piston including a valve chamber formed in said piston, a fluid controlling valve arranged in said valve chamber for controlling fluid flow to the opposite ends of said cylinder, and passage means for supplying pressure. fluid from the valve chamber at the forward side of the valve to the rear end of the cylinder and from the valve chamber at the rear side of the valve to the forward end of the cylinder, pressure fluid being supplied to said valve chamberfrom said constant pressure chamber through said tubular portion, said valve having an axial passage through which fluid flows to one end o-f said cylinder.

11.- In a pressure fluid motor, a cylinder, a piston reciprocabletherein, and fluid distribution v means for effecting reciprocation of saidv piston including a valve chamber formed in said piston, a fluid actuated fluid distributing valve movably guided in said chamber, and passage means controlled by said valve for supplying pressure fluid to the opposite ends of said cylinder including passages formed in said piston and leading from the. forward `end. of said Valve chambery to the rear end of the cylinder 4and passages formed in said piston and leading from the rear end of Vthe valve chamber' to the forward end of said valve chamber for connecting said axial passage means with the inner ,ones of said concentric grooves for supplying pressure fluid constantly to said inner grooves, said valve sealing the outer boundary of one or the other of said inner grooves when in its opposite positions, and passages connecting the outer grooves Withthe. opposite ends of thefcylinder, said passages each connecting its respective groove-with the cylinder end which is the more remote lfrom ysaid groove.

13. In a pressure fluid motor, a cylinder, a piston reciprocable therein, and 4fluid distribution means for effecting reciprocation of vsaid piston including a valve chamber formed in said piston, a fluid actuated fluid distributing valve reciprocable in said chamber, said valve having end seat- ,y

ing surfaces and annular pressure areas surrounding said seating surfaces, passage means controlled by.l said valve for supplying pressure fluid from said valve chamber to the opposite ends of said cylinder, and means for throwing `said valve into its different operating positions including means for supplying pressure fluid to said annular pressure areas on said valve.

14. In a pressure fluid motor, a cylinder, a piston reciprocable therein, and fluid distribution means for effecting reciprocation of said piston including a valve chamber formed in said piston, a fluid distributing valve arranged in said valve chamber to reciprocatein the direction of reciprocation of said motor piston, yand passage means controlled by said valve for supplying pressure fluid to said cylinder, said passagefmeans arranged with respect to said valve and said `valve Ybeing arranged in said chamber so that said valve seats in a forward position when the piston strikes -its blow thereby to prevent unseating of the valve by inertia action.

r15. In a pressure fluid motor,l a cylinder, a piston reciprocable therein, and fluid distribution -means for effecting reciprocation of said piston including a valve chamber formed in said piston,

va fluid distributing valve-arranged in said valve chamber for controlling fluid flow through` said pistonjto theopposite ends of the cylinder, and

passage means controlled by said valve for supplythe vinterruption of the movement of the piston y.

upon the striking of its blow presses said valve `toward reverse-flow effecting position;

16. In a'pressure fluid motor, a cylinder,` a piston reciprocable therein, and fluid distributing means for effecting reciprocation of said piston including a valve chambery formed in said piston,

a fluid distributing valve arranged in said valve chamber for movementk therein, and passage means controlled by ysaid valve for supplying pressure fluid to said cylinder, said valve chamstrikes at its extremes of movement, said passage means varranged with respect to said valve and saidabutments arranged and said valve guided so that reversals of piston travel tend only to maintain jsaid valve in its positions peculiar to such reversals of travel. l

ELMER G. GARTIN.

-ber providing abutments against which said valve 

